Reviewed to comply with lua guidelines

technic/tools/lawn_trimmer.lua

@@ -1,27 +1,33 @@
 --[[
-	The Lawn Trimmer, also known as Weed Whacker, is a common gardening power tool.
-	In minetest, it has several uses. While it removes all members of 'flora' group
-	and can be used for literally mowing grass or trimming it around vegetable beds,
-	it's not its most important application.
+	The Lawn Trimmer, also known as Weed Whacker, is a common gardening power
+	tool. In minetest, it has several uses. While it removes all members of 
+	'flora' group and can be used for literally mowing grass or trimming it 
+	around vegetable beds, it's not its most important application.
    
-	1. The tool can be used when searching for plants that can be cultivated in the wilderness.
-	Some of them are hard to see through grass; some of them are hard to tell from the grass;
-	some of them are actually obtained by removing the grass (e.g. barley seeds).
+	1. The tool can be used when searching for plants that can be cultivated 
+	in the wilderness. Some of them are hard to see through grass; some of 
+	them are hard to tell from the grass; some of them are actually obtained
+	by removing the grass (e.g. barley seeds).
    
-	2. Producing organic dye pigments. While growing flowers is a matter of fertilizing the soil
-	with bone meal, harvesting them by hand is a chore.
+	2. Producing organic dye pigments. While growing flowers is a matter of 
+	fertilizing the soil with bone meal, harvesting them by hand is a chore.
    
 	In both scenarios, the tool will be very handy for the player.
-	It comes with 4 modes of operation, defined by how wide its sweep is: from 0 (at one's feet)
-	to 3 nodes in radius (square radius, as most things in minetest are).
+	It comes with 4 modes of operation, defined by how wide its sweep is: 
+	from 0 (at one's feet) to 3 nodes in radius (square radius, as most 
+	things in minetest are).
 
-	The sound is an edited fragment from https://www.cutestockfootage.com/sound-effect/9251/grass-trimmer-01
-	used in accordance with its licensing terms (free use for any purpose in an altered form)
+	The sound is an edited fragment from 
+	https://www.cutestockfootage.com/sound-effect/9251/grass-trimmer-01
+	used in accordance with its licensing terms (free use for any purpose in
+	an altered form)
 ]]
 
 -- Configuration
-local lawn_trimmer_max_charge        = 10000 -- default: 10000 - Same as the chainsaw
-local lawn_trimmer_charge_per_object = 25    -- default: 25    - Can mow 400 'group:flora' blocks
+-- Intended to hold as much as the chainsaw, 10000 units
+local lawn_trimmer_max_charge        = 10000
+-- With 25 units per object can mow 400 'group:flora' blocks
+local lawn_trimmer_charge_per_object = 25
 
 local S = technic.getter
 
@@ -35,23 +41,24 @@ local lawn_trimmer_mode_text = {
 
 -- Mode switcher for the tool
 local function lawn_trimmer_setmode(user,itemstack)
-	local player_name=user:get_player_name()
-	local meta=minetest.deserialize(itemstack:get_metadata())
+	local player_name = user:get_player_name()
+	local meta = minetest.deserialize(itemstack:get_metadata())
 
-	if meta == nil then
+	if not meta then
 		meta = {mode = 0}
 	end
-	if meta.mode == nil then
-		minetest.chat_send_player(player_name, S("Use while sneaking to change Lawn Trimmer modes."))
+	if not meta.mode then
+		minetest.chat_send_player(player_name, 
+			S("Use while sneaking to change Lawn Trimmer modes."))
 		meta.mode = 0
 	end
+	
 	meta.mode = meta.mode + 1
+	if meta.mode > 4 then meta.mode = 1 end
 	
-	if meta.mode > 4 then 
-		meta.mode = 1 
-	end
-	
-	minetest.chat_send_player(player_name, S("Lawn Trimmer Mode %d"):format(meta.mode) .. ": " .. lawn_trimmer_mode_text[meta.mode])
+	minetest.chat_send_player(player_name, 
+		S("Lawn Trimmer Mode %d"):format(meta.mode) .. ": "
+		.. lawn_trimmer_mode_text[meta.mode])
 	itemstack:set_name("technic:lawn_trimmer_" .. meta.mode);
 	itemstack:set_metadata(minetest.serialize(meta))
 	return itemstack
@@ -66,10 +73,10 @@ local function trim_the_lawn(itemstack, user)
 	if not meta or not meta.mode or keys.sneak then
 		return lawn_trimmer_setmode(user, itemstack)
 	end
-	
 	if not meta or not meta.charge then
 		return
 	end
+	
 	if meta.charge > lawn_trimmer_charge_per_object then
 		minetest.sound_play("technic_lawn_trimmer", {
 			to_player = user:get_player_name(),
@@ -80,28 +87,34 @@ local function trim_the_lawn(itemstack, user)
 	local pos = user:getpos()
 	local inv = user:get_inventory()
 	-- Defining the area for the search needs two positions
+	-- The tool has a limited range in the vertical axis, which is capped at +/- 1 node
 	local start_pos = {
 		x = pos.x - meta.mode + 1,
 		z = pos.z - meta.mode + 1,
 		y = pos.y - 1 
-	} -- the tool can hardly be lowered a lot while standing, but we'll allow 1 node
+	} 
 	local end_pos = {
 		x = pos.x + meta.mode - 1,
 		z = pos.z + meta.mode - 1,
 		y = pos.y + 1
-	} -- cannot be raised too high either, though mostly for safety reasons
+	} 
 
-	-- Since nodes sometimes cannot be removed, we cannot rely on repeating find_node_near() and removing found nodes
+	-- Since nodes sometimes cannot be removed, we cannot rely on repeating 
+	-- find_node_near() and removing found nodes
 	local found_flora = minetest.find_nodes_in_area(start_pos, end_pos, {"group:flora"})
 	for _,f in ipairs(found_flora) do
-		if meta.charge < lawn_trimmer_charge_per_object then break end -- no charge left for this node
-		if minetest.is_protected(f, user:get_player_name()) then break end -- may not dig this node
+		-- Abort if no charge left for a node
+		if meta.charge < lawn_trimmer_charge_per_object then break end
+		-- Skip to the next one if this node cannot be dug
+		if not minetest.is_protected(f, user:get_player_name()) then
 			meta.charge = meta.charge - lawn_trimmer_charge_per_object
 			local node = minetest.get_node_or_nil(f)
 			minetest.node_dig(f, node, user)
 		end
+	end
 	
-	-- the charge won't expire in creative mode, but the tool still has to be charged prior to use
+	-- The charge won't expire in creative mode, but the tool still 
+	-- has to be charged prior to use
 	if not technic.creative_mode then
 		technic.set_RE_wear(itemstack, meta.charge, lawn_trimmer_max_charge)
 		itemstack:set_metadata(minetest.serialize(meta))
@@ -121,29 +134,30 @@ minetest.register_tool("technic:lawn_trimmer", {
 	on_use = function(itemstack, user, pointed_thing)
 		trim_the_lawn(itemstack, user)
 		return itemstack
-	end,
+	end
 })
 
-for i=1,4,1 do
-	technic.register_power_tool("technic:lawn_trimmer_"..i, lawn_trimmer_max_charge)
-	minetest.register_tool("technic:lawn_trimmer_"..i, {
+for i = 1,4,1 do
+	technic.register_power_tool("technic:lawn_trimmer_" .. i, lawn_trimmer_max_charge)
+	minetest.register_tool("technic:lawn_trimmer_" .. i, {
 		description = S("Lawn Trimmer Mode %d"):format(i),
-		inventory_image = "technic_lawn_trimmer.png^technic_tool_mode"..i..".png",
+		inventory_image = "technic_lawn_trimmer.png^technic_tool_mode" .. i .. ".png",
 		wield_image = "technic_lawn_trimmer.png",
 		wear_represents = "technic_RE_charge",
 		on_refill = technic.refill_RE_charge,
-		groups = {not_in_creative_inventory=1},
+		groups = {not_in_creative_inventory = 1},
 		on_use = function(itemstack, user, pointed_thing)
 			trim_the_lawn(itemstack, user)
 			return itemstack
-		end,
+		end
 	})
 end
 
 
 -- Provide a crafting recipe
 local mesecons_button = minetest.get_modpath("mesecons_button")
-local trigger = mesecons_button and "mesecons_button:button_off" or "default:mese_crystal_fragment"
+local trigger = mesecons_button and "mesecons_button:button_off" 
+	or "default:mese_crystal_fragment"
 
 minetest.register_craft({
 	output = 'technic:lawn_trimmer',